Detachable keyboard for transposing music on pianos



l; Tow. DETACHABLE KEYBOARD FOR TRANSPOSING MUSIC 0N PIANOS.

l APPLICATION FILED FEB. I2.-192I 1,392,883. Patented Oct. 4, 1921.

Isidore v779W z. row,

DETACHABLE KEYBOARD FOR THANSPOSING MUSIC 0N PIANOS. APPucmoN man its.12. 1921.

2 SHEETS- 1,392,883. Patented 00u 4, 1921.

' i l suegra.

mvENToR Z'alclore a1F01/v BY HIS ATTORN UNITED STATES PATENT OFFICE.

ISIDORE TOW, 0F NEW YORK, N. Y.

DETAGHABLE KEYBOARD Eon' TRANsPosING MUSIC oN PIANos.

Specicaton of Letters Patent.

Patented 0ct.4, 1921.

Applcationled February l12, 1921. Serial No. 444,456.

v portable.

Second: To have said transposing 'means convenient to handle and easytoattach to and detach from any piano. f j

Third: To enable said transposing means to transpose to all musicalkeys, major'or minor.

Fourth: `To have said transposing means simple, durable and inexpensive.Y

I attain these objects bythe detachable keyboard illustrated in theaccompanying drawings or by any mechanical equivalent or obviousmodification of the same.

In the drawings Figure 1vis afsection on the line A-B 'of Fig-2; Fig. 2is a plan of the stationarylower part orvframe of my detachablekeyboard. Fig. 3 is a view partly'in` elevation, partly in section,show

ing the box 53, hereinafter described, inV

position on the depressed end key of the piano.

Similar numerals refer to similar parts throughout the several views. l

11 designates thestationary frame of my detachable keyboard fortransposing music on pianos; said frame contains the vertical web orbeam 11, and the horizontal flange 11' at the 'lower end of said `frame11 has the rail-or track v12 secured'thereto 'by -means of the rivet orscrew 64.

13-14 isonejof 'a pair of carriers,`shown in Fig. 1 as'built up of theangle bars 13 and'14by means of rsuitable iastveningls,,`

which are omitted `forvthe sake'of clearness; these'carrie'rs 'have'each a groove 'on its underside adaptedtoV slidabl'y fit the verticalweb or ridge on the track 12, as shown in Fig. 1. .A

Said carriers 13-14 are secured to the underside of the bridge 16, whichrests thereon and Vis parallel ornearly so to the substantiallyhorizontal iange 11 of `the iframe 11, and it extends almost but notquite through theJ entire length of said frame 11, which has itsendssecured to the boxes 53 and 5,3 of which the box 53 isshown in Fig. 2,and 53 is shown in Fig. 1, and which have at their rear the extensions54 and 54" res ectively. I

aid boxes 53 and 53 serve as supports for the frame 11', andthey areadapted to lit over the end keys of any piano, and the extensions 54 and54 maybe inserted into the openings formed in the front 67-66 of thepiano over the end keys 70 when the lat,

ter are depressed until they touch the bottom 68 of the keybox, as shownin Fig. 3; the' boxes 53 and 53 with their extensions 54 and 54 are thensecured inpl'ace, if desired, bymeans of the tongues 49, which.

terminate at their rear ends in the spurs 51,

'which tongues are pivotally `connected to said boxes, inside thereof bymeans ofthe pins 50, as shown in Fig. 1, and they are provided withthenuts 47 and clampscrews ing its lower end anchored in the base 4"48, andtheyfare provided with the collars 59 above the to'psof said boxes 53and 53. Y

. 46, one of which is 'shownin Fig. y1 as hav- Bv turning the caps 46 ofsaid screws V 46, the tongues 49 may be raised andk pressed a rainst thetops of said openings in the front `6 66 of the piano, therebysecuringsaid boxes 53 and 53 in place; the spurs 51 aid vto prevent thedisengagement of said exten- "sions 54 and 54l fromv said openings; 52isa i groove in the upper surfaceA of each of said extensionsj53 and53for the ends of said tongues 49 to rest therein.

Said boxes 53"and 53` are secured to said frame 11 by means of the angleplates 37, which may have their vertical anges se cured to thestiilening bar 25ct said frame 11 on the front or yinside thereof; therear or outer side of said frame 11 may be covered with a coat offelting 15 to prevent scratching of the iront 67 of the piano.

The 'horizntal iange of each of said angles 37 is shown in Fig.,2 ashaving there- `in the slot 45, whereby it is adapted to slide on thestud .43, which is secured to the upper plate 38 of each of said boxes53 and 53', and it may be retained in position bymeans of the nut 44,this enables the b'oxes 53 Yand 53 with their extensions 54 and 54 tobe moved to the left in the drawings, when my detachable keyboard is tobe packed up for portability, until said extensions are well under theframe 11.

Said upper plate 38 is pivotally connected to the lower plate 40 of eachbox by means of the hinges 39 consisting each of the pin 61 and thesocket 62.

The leveling screws 41,pass each through a tapped hole in the plate 38,and it extends through an opening in the plate 40 into the interior ofeach box 53 and 53', where it is anchored in the pivotal bearing 42,which is secured to each of said boxes by means of the screws 60; thecollar 65 is secured to said screw 41 above said bearing 42.

By turning the screws 41 the plate 38 may be turned around the pivot 39into any required angular position with relation to the plate 40 of theboxes 53 and 53, thereby causing the front edge of the flange 11 of theframe 11 to'be raised or lowered as may be required; as the end keys ofthe piano on which said boxes 53 and 53 rest, may not always, whendepressed, be inclined the same angular degree or amount.

The above described clamp-screws 46 pass freely through the slots 45 inthe plates 37 and through an opening in each of the plates 38 and 40,whereby the adjustment of the angular position of the boxes 53 and 53does -not interfere with said clamp screws 46,

nor is it interfered with by them.

The box 53 has mounted thereon the housing 55 inclosing a pair of bevelgears 56 and 57,- the former being connected to the horizontal leadscrew 32 and the latter to the vertical operating rod 58, by means ofwhich said lead screw `may be turned; said operating rod 58-extendsthrough the top of said housing 55.

Said lead screw 32 actuates the nut 33, which is secured to thetraveling bridge 16, which carries the set of white keys 19 and blackkeys 2O of usual design.

The joint or knuckle of each of said keys has therein an oblong opening21, which incloses the post 17, which is at its lowerV end secured tothe bridge '16, as shown in Fig. 1; the upper ends of said posts 17 areconnected by means of the horizontal binding rod 18, against which thetops of said knuckles or joints are abutting; the openings 21 of saidknuckles are long enough to permit an ample degree of oscillation'forsaid keys.

The under side of said knuckles is padded on said bridge with felting orsome other soft material.

19 is the tip of each of said keys 19.

Each key 19 and 2O is normally kept in position by means of the platespring 31, which is secured at its lower end to said bridge 16, andV ithas the key resting on its Von the rear thereof.

upper end, thereby permitting the key to slide thereon when said key isdepressed by the fingers of the pianist.

Each of said keys 19 and 20 has secured thereto the rod 22, whichextends through one of the slots 23 in said bridge 16 and has at itslower end the shoe 24 which may be made of soft rubber or any othersuitable material.

The rods 22 are all of the same length to permit the ready traveling ofthe bridge 16 over the keyboard of the piano, and the shoes 24 at thelower ends of said rods are close to the upper surface of the black keysof the piano, which they are adapted to actuate, when the keys on thebridge 16 are depressed by the pianist.

To reach the white keys of the piano, I provide the iiller blocks 35,which may be made of lfelting or some other soft material, and eachfiller block is secured to the front end of one of the strips 34, whichis pivotally .connected at its rear end to one of the bearings 29 at thefront edge of the flange 11 by means of the rod 20.

The rear ends of said strips 34 have also the f orm of the bearing 29,and each of these bearings has the spur 36 extending rearwardlytherefrom and adapted to abut against the under side of the fiange 11 ofthe frame 11 when said filler block is in its lowest position, therebypreventing the undue dropping of said filler blocks when said frame 11is off the piano.

Each of said filler blocks rests on a white key 69 of the piano, and thetops of the filler blocks aie on the same level with the tops of theblack keys of the piano.

The rods 22 actuate the white keys 69 of the piano through said fillerblocks 35, and said rods are carefully spaced, so as not to actuate morethan one key at a time.

To keep the front of the bridge 16 from tilting forward, I provide theangle plates 26, the horizontal part of each of which is secured to thebridge 16, and the vertical part has its upper edge in sliding contactwith the inside of the fiange 112 of the frame 11, with the strip offelting 27 interposed therebetween.

Said angle plates 26 pass through notches or slits in the verticalflange of the bridge 16, which has the pointer 28 secured thereto Theupper end of said pointer is close to the flange 112 and top of theframe l1,

which have the index lines 63 of all the musical keys marked thereon.

It is evident that when it is necessary to transpose to a certainmusical key, all the pianist has to do is to move the bridge 16 by meansof the operating rod 58 and the lead screw 32 until the pointer 28reaches the required index line on the flange 112 and top of the frame11; the movable set of-.keys 19,-20 is then played on from the notes asusual, and the music will be higher or lower to the extent that the setof movablekeys is displaced with relation tothe stationary or pianokeys.

To make my detachable keyboard more convenient in handling, especiallywhen carried abroad, I propose to make the frame 11 and the bridge 16 inmultiple sections, which may readily be folded up for packing into acase and assembled again for attaching to any piano whenever required.

The'sections may be joined together by suitable splicing bars andinterlocked by proper pins and notches on said splicing bars and in thesections.

Many changes could be made in the details of my detachable keyboard fortransposing music on pianos without'departing from the main scope of myinvention; I do not, therefore, restrict myself to the details as shownin the drawings; but I intend to include also all mechanical equivalentsand reasonably obvious modifications of the same within the scope of myinvention.

What I claim as my invention, and desire to secure by Letters Patent is:

1. In a detachable keyboard for transposing music on pianos, astationary frame adapted to extend over the keyboard of a piano, abridge slidably connected to said frame, a set of keys on said bridge,adapted to actuate the piano keys, and a means for raising or loweringthe front edge of said frame, thereby adjusting the proper angle ofinclination of said frame to said piano.

2. In a detachable keyboard for transposing music on pianos, a pair ofsupporting members adapted to lit over the end keys of a piano, andhaving extensions adapted to be inserted into the openings formed in thefront of the piano over said end keys, when the latter are depressed, astationary frame connected at its ends to said members, a bridge,slidably connected to said frame, and a set of keys on said bridgeadapted to actuate the piano keys.

3. In a detachable keyboard for transposing music on pianos, astationary frame adapted to extend over the keyboard of a piano, asubstantially horizontal flange on said frame, a track mounted on saidflange, multiple carriers in sliding contact with said track, a bridgemounted on said carriers and a set of keys on said bridge adapted toactuate the piano keys.

4. In a detachable keyboard for transposing music on pianos, astationary frame adapted to extend over the keyboard of a piano, abridge slidably connected to said frame, a set of keys on said bridge,springsy for supporting said keys, suitable slots in said bridgeopposite the underside of said keys, rods connected to said bridge keys,said rods extending through said slots and shoes of soft material at theIlower ends yof said rods, below said slots, said rods with said shoesbeing Vadapted to actuate the piano keys whenthe bridge ykeys aredepressed, andsaid shoes beingadapted to abut against the under sideofthe bridge, thereby limiting the upward thrust of said keys bysaidsprings.

5. In a detachable keyboard for transposing music on pianos a stationaryframe adapted to extend over the keyboard of a iano, a bridge slidablyconnected to said flame, a set of keys on said bridge, rods connected tosaid bridge keys, said rods being of substantially the same length andtheir lower ends normally reaching down almost to the surface of theblack keys of the piano, filler-blocks of soft material over the whitekeys of the piano under said rods, connecting strips secured at theirfront ends to said filler blocks and at their rear ends pivotallyconnected to the front edge of said frame and spurs at the rear ends ofsaid strips adapted to abut against the under side of said frame,thereby limiting the drop or inclination of said strips when said frameis off the piano.

6. In a detachable keyboard for transposing music on pianos a pair ofsupporting members adapted to fit over the end keys of a piano andhaving extensions adapted to be inserted into the openings formed in thefront of the piano over said end keys, when the latter are depressed, astationary frame connected at its ends to said members, said framecomprising a vertical beam and a horizontal flange at the lower edgethereof, said vertical beam terminating at its upper edge in an innerflange, a bridge slidably connected to said frame, a set of keys on saidbridge adapted to actuate the piano keys, one or more angle platesconnected at their horizontal webs to said bridge and having theirvertical webs in sliding contact with said inner flange, thereby keepingthe front of the bridge from tilting forward.

7. In a detachable keyboard for transposing music on pianos a pair ofsupporting members adapted to fit over the end keys of a piano andhaving extensions adapted to be inserted into the openings formed in thefront ofthe piano over said end keys, when'the latter are depressed, astationary frame connected at its ends to said members, said framecomprising a vertical beam and a horizontal flange, a bridge slidthefront of the piano over said end keys, for normally keeping said membersin place when the latter are depressed, a stationary with relation tqsadframe, a bridge slidably frame, connected at its ends to said members,connected t0 said frame and a set of keys on 10 a means for slidablyconnecting said memsaid bridge adapted to aetuate the piano bers withtheir extensions to said frame keys. a

transversely thereto t0 facilitate the packing up of the detachablekeyboard, a means ISIDORE TOW.

